stack/apps/web/src/hooks/useWebSocket.test.tsx

import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
import { renderHook, act, waitFor } from "@testing-library/react";
import { useWebSocket } from "./useWebSocket";
import type { Socket } from "socket.io-client";
import { io } from "socket.io-client";

// Mock socket.io-client
vi.mock("socket.io-client");

describe("useWebSocket", (): void => {
  let mockSocket: Partial<Socket>;
  let eventHandlers: Record<string, (data: unknown) => void>;

  beforeEach((): void => {
    eventHandlers = {};

    mockSocket = {
      on: vi.fn((event: string, handler: (...args: unknown[]) => void) => {
        eventHandlers[event] = handler;
        return mockSocket as Socket;
      }) as unknown as Socket["on"],
      off: vi.fn((event?: string) => {
        if (event && Object.hasOwn(eventHandlers, event)) {
          // eslint-disable-next-line @typescript-eslint/no-dynamic-delete
          delete eventHandlers[event];
        }
        return mockSocket as Socket;
      }) as unknown as Socket["off"],
      connect: vi.fn(),
      disconnect: vi.fn(),
      connected: false,
    };

    (io as unknown as ReturnType<typeof vi.fn>).mockReturnValue(mockSocket);
  });

  afterEach((): void => {
    vi.clearAllMocks();
  });

  it("should connect to WebSocket server on mount", (): void => {
    const workspaceId = "workspace-123";
    const token = "auth-token";

    renderHook(() => useWebSocket(workspaceId, token));

    expect(io).toHaveBeenCalledWith(expect.any(String), {
      auth: { token },
      query: { workspaceId },
    });
  });

  it("should disconnect on unmount", (): void => {
    const { unmount } = renderHook(() => useWebSocket("workspace-123", "token"));

    unmount();

    expect(mockSocket.disconnect).toHaveBeenCalled();
  });

  it("should update connection status on connect event", async (): Promise<void> => {
    mockSocket.connected = false;
    const { result } = renderHook(() => useWebSocket("workspace-123", "token"));

    expect(result.current.isConnected).toBe(false);

    act(() => {
      mockSocket.connected = true;
      eventHandlers.connect?.(undefined);
    });

    await waitFor(() => {
      expect(result.current.isConnected).toBe(true);
    });
  });

  it("should update connection status on disconnect event", async (): Promise<void> => {
    mockSocket.connected = true;
    const { result } = renderHook(() => useWebSocket("workspace-123", "token"));

    act(() => {
      eventHandlers.connect?.(undefined);
    });

    await waitFor(() => {
      expect(result.current.isConnected).toBe(true);
    });

    act(() => {
      mockSocket.connected = false;
      eventHandlers.disconnect?.(undefined);
    });

    await waitFor(() => {
      expect(result.current.isConnected).toBe(false);
    });
  });

  it("should handle task:created events", async (): Promise<void> => {
    const onTaskCreated = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onTaskCreated }));

    const task = { id: "task-1", title: "New Task" };

    act(() => {
      eventHandlers["task:created"]?.(task);
    });

    await waitFor(() => {
      expect(onTaskCreated).toHaveBeenCalledWith(task);
    });
  });

  it("should handle task:updated events", async (): Promise<void> => {
    const onTaskUpdated = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onTaskUpdated }));

    const task = { id: "task-1", title: "Updated Task" };

    act(() => {
      eventHandlers["task:updated"]?.(task);
    });

    await waitFor(() => {
      expect(onTaskUpdated).toHaveBeenCalledWith(task);
    });
  });

  it("should handle task:deleted events", async (): Promise<void> => {
    const onTaskDeleted = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onTaskDeleted }));

    const payload = { id: "task-1" };

    act(() => {
      eventHandlers["task:deleted"]?.(payload);
    });

    await waitFor(() => {
      expect(onTaskDeleted).toHaveBeenCalledWith(payload);
    });
  });

  it("should handle event:created events", async (): Promise<void> => {
    const onEventCreated = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onEventCreated }));

    const event = { id: "event-1", title: "New Event" };

    act(() => {
      eventHandlers["event:created"]?.(event);
    });

    await waitFor(() => {
      expect(onEventCreated).toHaveBeenCalledWith(event);
    });
  });

  it("should handle event:updated events", async (): Promise<void> => {
    const onEventUpdated = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onEventUpdated }));

    const event = { id: "event-1", title: "Updated Event" };

    act(() => {
      eventHandlers["event:updated"]?.(event);
    });

    await waitFor(() => {
      expect(onEventUpdated).toHaveBeenCalledWith(event);
    });
  });

  it("should handle event:deleted events", async (): Promise<void> => {
    const onEventDeleted = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onEventDeleted }));

    const payload = { id: "event-1" };

    act(() => {
      eventHandlers["event:deleted"]?.(payload);
    });

    await waitFor(() => {
      expect(onEventDeleted).toHaveBeenCalledWith(payload);
    });
  });

  it("should handle project:updated events", async (): Promise<void> => {
    const onProjectUpdated = vi.fn();
    renderHook(() => useWebSocket("workspace-123", "token", { onProjectUpdated }));

    const project = { id: "project-1", name: "Updated Project" };

    act(() => {
      eventHandlers["project:updated"]?.(project);
    });

    await waitFor(() => {
      expect(onProjectUpdated).toHaveBeenCalledWith(project);
    });
  });

  it("should reconnect with new workspace ID", (): void => {
    const { rerender } = renderHook(
      ({ workspaceId }: { workspaceId: string }) => useWebSocket(workspaceId, "token"),
      { initialProps: { workspaceId: "workspace-1" } }
    );

    expect(io).toHaveBeenCalledTimes(1);

    rerender({ workspaceId: "workspace-2" });

    expect(mockSocket.disconnect).toHaveBeenCalled();
    expect(io).toHaveBeenCalledTimes(2);
  });

  it("should clean up all event listeners on unmount", (): void => {
    const { unmount } = renderHook(() =>
      useWebSocket("workspace-123", "token", {
        onTaskCreated: vi.fn(),
        onTaskUpdated: vi.fn(),
        onTaskDeleted: vi.fn(),
      })
    );

    unmount();

    expect(mockSocket.off).toHaveBeenCalledWith("connect", expect.any(Function));
    expect(mockSocket.off).toHaveBeenCalledWith("disconnect", expect.any(Function));
    expect(mockSocket.off).toHaveBeenCalledWith("task:created", expect.any(Function));
    expect(mockSocket.off).toHaveBeenCalledWith("task:updated", expect.any(Function));
    expect(mockSocket.off).toHaveBeenCalledWith("task:deleted", expect.any(Function));
  });
});